Variable-feed gear



Patented Nov.. 2, 1925.

UNITE@ STATES PATENT @firfi CURT WOLF, OF LANGEBRUCK, GER-MANY, ASSGNOR T0 GETREBEBAU-GESELLSCHAFT MIT BESCHRAENKTER HAFTNG, 0F DRESDEN, GERMANY, A CORPORATON F GERMANY.

VARIABLE-FEED GEAR.

Application filed January 26, 1926, Serial No 83,902, and in Germany February 1G,l 1925.

This inventionrelates to a feed gear having a variable feed stroke and being actuated by pairs of eccentrics formed by members that can beadjusted relatively7 to each other.

I am aware of the factthat there exist already feed gears having a variable stroke and being operated by eccentrics, the eccen tricity of which can be adjusted in order to vary the feed stroke. The individual eccentrics used in connection with said known gears consist of two members that can be adjusted relatively to one another for the purpose of varying the eccentricity. With the constructional forms of said gears that have become known up to now the two members constituting an eccentricare so arranged relatively to each other that at normal running one of said two members is carried round. by the other. Vhen these members are. to, be adjusted relatively to each other in order to change the length of the stroke,` the pressure existing between the said two members gives rise to a very great friction whereby the adjustment is rendered difficult.

This drawback is overcome by the present invention, the gist of which resides therein that the two members constituting an eccentric are operated separately. Villien each of the individual eccentrics is composed of an inner eccentric disk and of an eccentric ring encompassing said disk and being adapted to be turned relatively thereto for the purpose of varying the stroke, itis, by this arrangement, rendered possible to affix the eccentric disks to the driving shaft/,whereas theeccentric rings are driven by the same shaft and with the same speedl by the intermediary' of a suitable separate gearing, for instance a cog-wheel gearing, 4whereby the arising of friction between the two members of each eccentric is obviated sothat they can be adjusted very easily'with respect to each other.

My invention is illustrated diagrammatically and by way of example in the accompanyingdrawing in which Figure 1 is a plan of the device, partly in section, Figure 2 a side view, also partlyin section, and Figures 3-5 show several positions of the eccentric disk and the eccentric ring.

`On the drawing, 1 denotes a driving shaft, and 2 a bevel-wheel located loosely upon said shaft and provided on its circumferential surface with worm-teethturning thisrv portion" of the bevel-wheel 2 into a worin-'wheel 3. This latter wheel meshes with a worm 4'. Affixed to the shaft 1 is a hub 5 from which extend radial pivots 5a and 5b carrying loose bevel-wheels 6 and 7 meshing on oneside withthe bevel-wheel 2 and on the other side with a bevel-wheel 8. As the wheel 3' is prevented fromrotation by the worm Ll, the wheels Gand 7 are caused to rotate when being carried round by the members 1, 5, 5a and 5b, and the rotary motion is transmitted to the wheel 8, which makes double the number Vof revolutions of the shaft 1f. The wheel 8 sits loosely upon the shaft 1, but is firmly` connected with" a spur-wheel 9 meshing with a spur-wheel 10 of the-same diameter affixedto ashaft 11 extending parallelly to the shaft 1 and serving as countershaft.

I wish it to be understood that the gearing described in the preceding paragraph, except the counter-shaft 11 with'` its cogwheel 10, can bereplaced by any other suitable gearing, adapted to rotate said wheel 10 and the shaftll.V n

This shaft is provided with a plurality of spur-wheels 12, of which'there are seven in the constructional formshown by way of example. These' wheels mesh with spur wheels 13 located loosely upon the shaft 1 and holding between them eccentric disks 14;, of which there are six in the example shown and which are keyed to the shaft 1. These disks are disposed in staggered arrangement around said shaft with respect totheir eccentric-ity, and each is encompassed by, and enclosed in', an eccentric ring 15 having a radial slot 20a (Figs. 2-5) engaged by a pin 2O supported in. the adjacent two cogwheels 13. Each disk 15 is located ina memberl@ provided firstly, with an'annular lining 21 which forms the support proper for the appertaining disk 15, and, secondly, with a lateralI lug ig., 2) by which, and by a pivot 17, itis hinged to a feed and locking gear described the next paragraph.

In the constructional form of this gear as illustrated by way of example the annular memberel is connected by the pin 17 with a similar annular member 19 supported rotatably upon ballsfor rollers 2S carried in recesses 27` provided in the circumferential surface of a disk 26 attacheclto the shaft 18. When the members 19 are moved in the one direction, also the shaft 18 will be turned, but if said members 19` are turned in the other direction, they get out of engagement with said shaft 18.

In consequence of the staggered arrangement of the eccentric disks 1a the shaft 18 will be continuously turned in one direction.

For the purpose of changing the direction of rotation of the driven shaft the following arrangement is made.

The shaft 18 carries also a loose cog-wheel 22, as well as a coupling sleeve 2&1 that can be shifted axially upon said shaft, but rotates with it, and can be coupled alternately with said wheel 22, as well as with `another bevel-wheel 25 fixed 0n a shaft 1ct. The wheels 22 and 25 mesh with a bevel-wheel 23 fixed on a shaft 30.V When the sleeve 241 has been shifted to the left so as to get coupled with the wheel 22, the wheel 22 drives the wheel 23 in the one direction, and as the coupling sleeve is rotated by the shaft 18, the rotatory motionwill be transmitted by said wheels 22 and .i3 to the shaft 30, while the wheel 25 now runs idly. lf the sleeve 211 is, however, shifted in the opposite direction the shaft 18 will be coupled with the wheel 25, and the wheel 23 and shaft 30 will be rotated in the opposite direction, while the wheel 22 will now run idly.

The shaft 1 is journaled in the bearings 31 and 32, the shaft 11 in the bearings 33 and 34, the shaft 18 in the bearings 35 and 36 and the shaft 18a in the one end of the shaft 18 and in the bearing 37 respectively.

Now, the manner of operation ofthe de vice is as follows: y

Supposing, the shaft 1 be rotated with any definite number of revolutions, the eccentric disks 14 will perform the same number of revolutions. The shaft 11, however, makes Adouble that number of revolutions in that ,1t is turned by the intermediary of the gear members 6, 7, 8, 9 and 10. Of course, also the wheels 12 which are firmly affixed to the shaft 11 are rotated with the same speed. The wheels 13 which are supported loosely upon the shaft 1 have double the circumference of the wheels 12 so that their number of revolutions corresponds to that of the shaft 1, and of the eccentric disks 111. New,

, as the eccentric rings 15 are coupled with the wheels 13 by the pins 20, also these rings rotate with the speed of the said disks. The motion of said eccentric members is being communicated to the members 16 which transmit it further to the feed locking gear carried by the shaft 18.

In the position of the parts shown in Figs. 1 and 2 the parts 14 and 15 are so positioned with respect to each other that the eccentrics composed each of one part 141- and one part 15 have no ecentricity, therefore the stroke of the members 16 is zero, that is to say, the shaft 18 is at rest. llVhen, however, the Worm 4 is rotated, that motion is transmitted by the members 2,6, 7, 8, 9, 10, 12,V

13 and 2O to the eccentric rings 15 upon the eccentric disks 14 while said disks 111- re-V main at rest. The pins 2O thereby get shifted in the slots 20L of said rings and the eccentricity of the eccentrics increases, whereby the members 16 are caused to perform a stroke, in consequence whereof the members 19 are caused to turnv forwardly and backwardly. l/Vhile the first of'these movements is going on, the rolls or balls 28 carry. the disk 26 round with them in known manner and the shaft 18 is rotated. It' the worm 4 is again turned, the eccentric rings 15 are shifted circumferentially further upon the eccentric rings 111 whereby the number of revolutions of the shaft .18 is again changed. It can be chane'ed from Zero up to the number of revolutions of the driving shaft 1. rlie change proceeds in every case'perfectly without friction, quickly, and noislessly.

I claim:

1. A variable feed gear, comprising, in combination, a driving shaft, a driven shaft, eccentrics connected with said driving` shaft,

adapted to transmit the movement to said driven shaft and composed each of two inemi bers, means foi' shifting said members relatively to one another thereby varying the degree of eccentricity of said eccentrics, and means for driving both members of said eccentrics independently from each other.

2. fr variable feed gear, comprising, in combination, a driving shaft, a driven shaft, eccentrica connected with said driving shaft, adapted to transmit themovement to said driven shaft and composed each of an inner eccentric disk and of an outer eccentric ring, means for turning said disks and rings relatively to each other; said disks being firmly secured to said driving shaft, and an intermediate gearing being so arranged and connected with said rings, as to be adapted to rotate these latter with the same number of revolutions as that of said driving shaft.

3. A variable feed gear, comprising, in combination, a driving shaft, a driven shaft,y eccentrics connected with said driving shaft. adapted to transmit the movement to said driven shaft and composed each of an inner` eccentric disk and of an outer eccentric ring, means for turning said disks and rings relatively to each othergsaid disksV being firmly secured to said driving shaft, cogwheels located loosely upon said shaft between said rings, pins secured to said wheels parallelly to their anis and engaging radial slots of the said rings, andan intermediate gearing being so arranged' and connected with said cog-wheels as to'be adapted toro-v tate these latter with`the same number of revolutions and in the same direct-ion as that of said driving shaft.

ln testimony whereof I have affixed my signature. l

CURT WOLF. 

